Fluid pressure regulator



Jan. 22, 1952 F N ESEMANN 2,583,006

FLUID PRESSURE REGULATOR Filed May 25, 1943 2 SHEETS-SHEET I III! , ZSnnentor FR/ TZ .lV/ESEMANN 05M$KW (Ittorneg Jan. 22, 1952 F. NIESEMANN FLUID PRESSURE REGULATOR 2 SHEETS-SHEET 2 Filed May 25, 1943 ALT/TIDE m FL'ET 3nventor FRITZ NE$MANN & a W

C(ttorneg Patented Jan. 22, 1952.

PATENT OFFICE FLUID PRESSURE REGULATOR ,Fritz Niesemanm Pittsburgh, Pa., assignor to Rockwell Manufacturing Company, a corporation of Pennsylvania Application May 25, 1943, Serial No. 488,370

This invention relates to fluid pressure regulators and relates in particular to'such regulators in which the outlet pressure characteristics are modifledto produce a desired outlet pressure and rate offio'w.

According to the present invention I provide in a pilot controlled valve comprising a main regulator and a second or'pilot regulator controlled from any desired source for supplying a loading pressure thereto which bleeds slowly to any desired point, means to separate the pilot regulator outlet pressure from the pilot regulator control pressure. The bleed opening may be located as desired. Where bleeding into the control pressure source is desired, a small bleed between the pilot regulator outlet pressure and the pilot regulator control pressure may be pro-' vided, this bleed being so small as to be sub- 'stantially without influence on the control presvalve member to provide a part or the whole bleed thereby greatly simplifying the structure. The area of the bleed orifice thus is uniform, and if desired, the bleed orifice may be made variable by suitably shaping the guide. This eliminates I the use of a stuillng box, sealing diaphragm, counterbalancing diaphragm or the like. Because of the small size of the pilot valve, the relatively small flow through the valve, and its relative small range of movement. I generally find it unnecessary to employ a balanced type of pilot valve member, although I do not intend to preelude such a pilot valve member from the present invention.

The main valve may be employed as a shut off valve by providing an on and oil? shut oil valve in the supply line or outlet line of the pilot regulator and arranging the structure so that when the pilot regulator supply line is shut oil. or the outlet is shut ofl', the loading pressure on the .main regulator falls below a predetermined minimum and a spring or other suitable means closes the mainvalve. The so called shut off valve in .the pilot-regulator supply or outlet line may be controlled by any suitable onand of! means or any suitable modulating-means such as a gas sure, and I mayutilize the guide for thepilot.

1 Claim, (01. 137.-153) valve thermostat or by an electrically operated thermostat valve, a timer or the like, and when operated --by some modulating means, the main regulator valve becomes a modulating valve operable as such throughout the whole range beltweenthe minimum and maximum, how of the v,izisuiator, or in any desired portion ofsuch range, depending among other things, upon the characteristics of the modulating action on the pilot 2 inlet or outlet. If desired, a minimum flow bypass around the shut off valve in the pilot flow may be provided, governed by an on and off valve. as for example a heat responsive pilot flame safeuard.

In the above described system or in the various modifications thereof, where the pilot regulator is controlled by the outlet pressure of the main regulator (it being understood that a burner, friction loss, or some other type of restriction is provided in the main regulator outlet beyond the point of connection of the pilot regulator thereto) the main regulator tends to maintain a constant or predetermined maximum pressure at the control point to which the pilot regulator is connected, and at ordinary atmospheric pressure this constant or predetermined maximum pressure will be a constant amount above atmospheric pressure, which amount will depend on the setting of the regulator. Where it is desired toyary the maximum outlet pressure of the main regulator, I vary the load on the pilot regulator so that a difierent control pressure becomes necessary to operate the pilot regulator valve and thus the main regulator tends to maintain a constant control pressure as required by the loading on the pilot regulator. This variation may be made dependent on a thermostat, pressure responsive device, or any suitable force or factor which, it is desired, shall govern the operation of the main regulator.

Where the pilot regulator is to be controlled by a variation in atmospheric pressure, I prefer to employ as the atmospheric pressure responsive element a piston, push rod, or the like having a vacuum on one side thereof and sealed by a flexible bellows or other type of flexible diaphragm, with a spring biasing said piston opposite the force of atmospheric pressure. Thus, a change in atmospheric pressure changes the force exerted by 'the spring, and the piston or push rod acts on the pilot loading spring to change the load on the pilot diaphragm, and in consequence change the outlet ressure of the main regulator.

The invention will be described in greater detail in the following specification taken in connection with the accompanying drawing, wherein are disclosed preferred embodiments of the invention by way of example, and wherein:

Figure l is a vertical sectional view of a preferred embodiment,

Figure 2 is a vertical sectional view of a detail of a further modification. and

Figure 3 is a curve graphically illustrating the performance of the apparatus.

Referring to the drawing, the valve housing I is made up of two parts comprising an outlet bowl 2 having an outlet opening 3 therein and a flat surface 3' which receives the inlet bowl 4 having an inlet opening 5. The two parts are secured together by screws 5. Inlet bowl 4 has a dividing wall 4' with openings 6 and 1 in which are located seat bushings 8 and. 8 with a pressed fit. Valve stem II extends through the bowl and has an upper flanged sleeve I2 acting as a stop and soldered or otherwise secured in proper location. A valve wing guide plate I3 and a flexible valve disk I4 engages the flange of sleeve I2. the valve disk seating, upon the inner edge of orifice bushing 8. At the lower end of the stem is located a similar flanged sleeve or stop member I6 and a flexible valve disk I1 and valve wing guide plate I8 are positioned on the sleeve and 4 the wing guides plates I3 and I8. The upper end of spring 36 abuts sleeve 38, limited against endwise movement by a stop pin 48 or the like, and thus the end of stem II is held against surface 34 of the diaphragm. Preferably sleeve 38 is of such length and is pinned to stem H in such position so that sleeve 38 engages sleeve 35 to limit downward movement of stem II, should thevalves fall wide open for any reason. The outlet bowl 2 has a boss 39 through which extends an opening 4| threaded at 42, and flanged bushing 43 is threaded into the hole 4| and serves to compress a gasket 45 between the diaphragm casing and outlet bowl 2 to prevent leakage at this point. There is thus provided a conduit or passage, 4| between the diaphragm control chamber 46 and the outlet opening 3. The

are retained by the fiange, thereof. If desired,

the valve wing guide may be integral with the valve disk. A spacer 22 receives the end of sleeve I2- and is held against the upper valve disk I4 by a spring 2| which at its lower end abuts the valve guide plate I8, and thus maintains the valves in separated position. The spacer 22 is separated a small amount from the upper end of sleeve I6 so as to allow for adjustment of nut 28, this space being small enough to prevent spacer 22 slipping off of sleeve I2. Spacer 22 prevents a sudden jolt from dislocating the valves and valve guides. A nut 20 threaded on the end of stem II positions the sleeve I6 relatively to sleeve I2 so that the valve disks I4 and I1 properly seat on orifice seats 8 and 9.

The valves are assembled to the stem by first placing sleeve I2 thereon and soldering it in I 29-and a cover 5|. Diaphragm plates 52 and 53.

position, and the valve guide plate I3 is placed on sleeve I2. Then valve disk I4 is inserted into theinlet bowl through inlet opening 5 and the stem II is passed through the valve opening in bushing 8 and through the opening in the valve I4. The spacer 22 then is slipped over the stem and the spring 2| passed over the spacer. The sleeve I6 is passed through the holes in lower valve I1 and lower wing plate I8 respectively and the assembly is then passed over the end of stem II which extends through the valve orifice in bushing 9. The nut 26 then is threaded on the stem I I and adjusted so that the valves I4 and 1 substantially simultaneously engage their respective seats, and the nut 28 is then soldered in position.

A diaphragm case 25 is suitably secured to one side of the valve case I upon a gasket 24 by screws (not shown) or other suitable means and has a central projecting portion 26 with an aperture 21 through which extends the valve stem II. The diaphragm 28 is suitably secured between the casing 25 and a cover 29, the diaphragm plates 3| and 32 being secured to the central portion of the diaphragm by a rivet 33 or the like, providing a substantial fiat surface 34.

Hole 21 is znade amply large so that any lateral movement of stem II will not cause the stem to engage or bind against the edges thereof, and flanged sleeve 35 fits over stem II was to partly close off or reduce the clearance area between the stem and hole 21, and one end of the spring 36 abuts this sleeve. Ample clearance is allowed portion 26 to allow any required lateral movement of sleeve 35 and stem II. the stem being guided for substantially rectilinear movement by chamber above the diaphragm 28 within the cover 29 is designated at 41 and may be called the loading chamber.

Cover 29 has a depression 48 which is covered by a diaphragm 49 clamped between the cover are secured at the center of the diaphragm 49 by a rivet 54 which provides a fiat surface 55 on the underside. A bore 62 extends through a boss 6| and has a valve orifice bushing 63 pressed therein to provide a valve orifice therethrough and a valve seat on the underside. A counterbore 56 receives a guide plate 51 with a pressed fit, and which has a central guide aperture 58 therein and the space or chamber in bore 56 below plate 51 communicates with loading chamber 51 by a bore 58. After the valve member 69 is inserted through bore 62 the bore is closed by a plug 64. A passage 65 extending through boss 6| into bore 62 connects by an external hose or pipe 66 through a hole 61 with the inlet Opening 5; The valve member 69 provides a tapered valve head 1| adapted to seat against valve bushing 63, and an enlarged stem portion 12 which fits the guide bore 58 with a relatively loose fit so as to allow free movement of the valve stem. The valve member has a head 14 which abuts the fiat surface 55 provided on diaphragm 49. A flanged cup or ferrule 15 on head 14 is engaged by spring 16 at one end, the other end of the spring abutting guide plate 51 so as to hold valve stem 69 against diaphragm 49.

Chamber 48, which may be designated as the pilot valve control chamber, is connected by a passageway 18 and a tube or hose 19 connected by opening 8| with the outlet opening 3. If desired this tube may open into bore 4|, thereby securing greater uniformity in pressure between chambers 48 and 46. Bore 59 and the space below guide member 51 may be considered the outlet of the pilot regulator. The flow from this outlet through the clearance between bore 58 and thickened portion 12 of the stem provides a bleed from chamber 41 into chamber 48 and through tube 19 into the outlet 3. This bleed should be small enough so as not to appreciably change the pressure in chamber 48 conducted thereto by tube 18, and thus the loading pressure in chamber 41 has no appreciable effect on diaphragm 49. If a larger bleed is desired than is provided by this clearance space, a hole 50 may be provided to the atmosphere, or holes may be provided in plate 51 or in any part of the wall of chamber 41 connecting into passageway 18. Where the bleed is not to atmospheric pressure I prefer to employ the spring 36 or some equivalent means to cause valves I4 and I1 to close when the pressure in chamber 46 falls. The chamber 82 above dia- '5 phragm, may be pressure chamber and is vented to the atmosphere by a vent 88.- Cover II has an extension 84 screw threaded externally at and bored and threaded The operation of the apparatus so far described will now be explained. Ordinarily, the outlet 8 of the regulator will be connected to an'apparatus such as a burner which provides a restric-.

' tion on flow from the outlet to the atmosphere, and itis desired that the pressure difference across this restriction be maintained constant.

designated in this particular modification as the atmospheric or barometric The inlet pressure at may be variable, and if drops lower than required to support diaphragm 48 against thisload, the diaphragm descends and opens valve II to allow a greater flow therethrough. 'This'flow comes from the high pressure side through conduits", 85 and bore 62, and passing through valve bushing 68 enters bore 56 and flows through bore 58 into chamber 41 faster than it can escape through the vents thereof and t us builds up a loading pressure in chamber 41 ichmoves diaphragm 28 and valve stem II do nward to open valves I4 and I1 and allow an incre ed flow into outlet-8. This increased flow in outlet 8 continues until the pressure in outlet 8 increases. and being transmitted to chamber 48 raises diaphragm 48 to allow spring 18 to close or throttle valve II. The pressure in chamber 4'! bleeds through the space around stem portion 12 into chamber 48, and'the control pressure in chamber 48 tends to maintain valve II in such position as to secure the desired relationship between the flow through valve orifice 83 and the bleed to m intain the desired pressure in chamberjlfor maintaining the desired condition in outlet 3. Thus, the pressure in chamber 41 i not necessarily constant but may be varied to maintain the pressure in outlet 8 constant, and the pressure in chamber 41 will not directly affect the control diaphragm 48. A decrease in pressure in chamber 4'! causes diaphragm 28 and stem II to be raised to close or throttle valves I4 and I1 I and an increase in pressure in chamber 41 causes the diaphragm and stem II to lower and open wider valves I4 and II. The pressure in outlet 8 will be determined by the force exerted by spring 88 upon diaphragm 48.

In applying the invention to the control of the air supply of a fuel burning heater for an aeroplane, the air inlet orifice for the burner becomes the restriction and the regulator will maintain a constant pressure difference across this restriction independent of the altitude of the aeroplane. However, at higher altitudes the specific gravity of the air changes, and as the burner requires a constant gravimetric flow of air to support combustion of a constant weight of fuel, the weight of air supplied to the burner will due to the lower specific gravity or the air.

the pressure difference across the restriction so that the gravimetric flowof air willbe sufficient to support combustion of the fueLand I will now describe the means by which this is accomplished.

In applying the invention to the control of the air supply of a fuel burning heater for an aeroplane, I provide a housing 88', which as shown, is made up of a cylindrical portion having. a head 8| and an internal flange 82 soldered thereon, anda hub 88 or the like, provides a shoulder 84 to which the flange 82 is soldered or otherwise secured in airtight relation. A sealing bellows is'soldered to one surface "of the hub and its other end is soldered to the flange 88 of a spring sleeve 88 to form a gas-tight chamber I8I and an interial chamber I88. This chamber IN is evacuated through tube 81 which is then crimped, fused and soldered or sealed in any other suitable manner. The sub 88 is threaded on the extension 85 of cover 5| and may be held in an established position by a locknut I82 and sealed in this position by a wire and lead seal. A stem I85 is secured to the lower end of the spring sleeve 88 and its lower end passes through a guide hole I88 in guide bushingill and into a'recess I81 in spring ferrule 84. A spring I88 in spring sleeve 88 abuts the sleeve and the cover 8I at its other end.

In operation the chamber I8I is evacuated and thus comprises an initial compression for spring I88 which depends upon the barometric pressure. The internal chamber I83 communicates with the atmospheric pressure chamber 82 through the hole I88 in bushing 81. casing 81 up or down on extension 85 the sleeve 88 may move upward to bring stem I85 out of engagement with spring ferrule 88 as indicated at A so that spring I88 will have no efiect upon spring 84 until a predetermined barometric pressure prevails in chamber I83. When the aeroplane reaches an altitude such that the barometric pressure allows' spring I88 to expand and bring stem I85 into contact with the ferrule 88, the spring 88 will be deflected to further load diaphragm 48 and thus require an increased pressure in the chamber 48 to balance diaphragm 48. Thus, a greater pressure willbe built up in outlet 3, with a consequent increase in pressure difierence across the restriction that increases the volume of air supplied to the fuel burner sufllciently to provide an approximately constant gravimetric flow.

In the modification shown in Figure 2', wherein like parts are correspondingly numbered, there is employed what I refer to as a characterized a'neroid. The cover II8 of the housing 88 has a stem III extending through the central boss, this stem being sealed with respect to the cover. The spring sleeve 88 has a similar boss 2 extending therefrom which may be integral with thesleeve, or separate therefrom and is secured in gas-tight relation, and a second spring H3 is introduced in the sleeve 88 and is guided by stems III and H2. This spring II8 is shorter than spring I88, and preferably is stronger and it is initially compressed to a lesser extent than spring I88 by evacuation of the chamber IN. The springs are so proportioned that before the full limit of downward movement of sleeve 88 is reached as shown by the dot and dash lines. the upper coil of spring I I3 moves entirely away from In applying the invention to a burner under such conditions. I provide means for increasing By. adjusting the" cover Ill, while spring I is still under'compression, so that thereafter only spring I00 acts to move the sleeve 09.

The action of the springs I00 and.Il3 will be more clearly understood by reference to the graph shown in Figure 3. In this graph in curves B and C the outlet pressure in inches of water is plotted against'the altitude in feet, and themovement or the aneroid element is plotted against vacuum. The curve B represents the outlet pressure requirement to maintain a constant gravimetric flow of gas. In the curve D the movement of stem I05 in inches is plotted against the force of springs I09 and I I3 in pounds. The curve C represents the-outlet pressure produced by the characterized aneroid assembly. Thus for example, if the case 90' (Fig. 1) is turned to bring stem I05 to the position A, the aneroid assembly will be without influence on the diaphragm 49 until the point E is reached and thus the outlet pressure up to this point will follow curve B. At this point however, the springs I08 and H3 come into play and modify the action of spring 90 to change the outlet pressure causing it to follow curve C until the point F is reached. At this point spring H3 has expanded to its free length and ceases to function and spring I08 alone deflects the spring 90 and thus causes the curve C to move at a diilerent angle'and increase the ratio of outlet pressure to altitude. By suitable selection of springs I08 and H3, or by employing more than two springs, the actual outlet pressure curve C may be made to conform approximately to the curve B at any desired point or points. The invention may be embodied in other specific forms without departure from the spirit or essential characteristics of the present invention. The specific form described herein therefore is to be considered in all respects as illustrative and not restrictive of the invention.

What is claimed and desired to be secured by United States Letters Patent is:

In a fluid controller, a main valve casing having main inlet and outlet connections and a dividing wall therebetween providing a valve orifice, a diaphragm and a cover secured to said casing providing main control and loading chambers on opposite sides of said diaphragm, valve means actuated by said diaphragm for controlling flow through said valve orifice from said inlet to said outlet, a passage connecting said main control chamber with said outlet, a second casing and a second diaphragm providing a pilot valve control chamber and an atmospheric pressure chamber on opposite sides of said second diaphragm, a conduit connecting said pilot valve control chamber with the main valve outlet, an inlet passageway in said second casing connecting said main loading chamber to the main valve inlet, a pilot valve in said inlet passageway operated by said second diaphragm, spring means for biasing said second diaphragm, a pressure responsive device mounted on said second casing camprising a diaphragm having an evacuated chamber on one side and an atmospheric pressure chamber on the other side thereof, means operated by said latter diaphragm engaging said latter spring means to vary the biasing action thereof for controlling pilot valve operation to vary the main valve outlet pressure as a result of changes in atmospheric pressure, and a plurality of springs of different effective lengths on one side of said latter diaphragm opposing the force of atmospheric pressure thereon for modifying the effect of said changes in atmospheric pressure upon the main valve outlet pressure in a predetermined manner.

FRITZ NIESEMANN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,173,834 Metzer Feb. 29, 1916 1,407,575 Prouty Feb. 21, 1922 1,489,811 Beggs Apr, 8, 1924 1,926,069 Sutton Sept. 12, 1933 1,927,727 Whitehurst Sept. 19, 1933 1,994,660 Painter Mar. 19, 1935 1,995,726 Soderberg Mar. 26, 1935 2,196,279 Thomas Apr. 9, 1940 2,313,149 Jacobsson Mar. 9, 1943 FOREIGN PATENTS Number Country Date 77,027 Germany Sept. 5, 1894 405,870 Great Britain Feb. 15, 1934 419,920 Great Britain Nov. 21, 1934 455,139 Great Britain Oct. 15, 1936 

